The short answer
For the web, lossless WebP: 20–40 % smaller than PNG with identical pixels. For editing masters, design hand-offs and anything opened in older tools, PNG. Convert PNG to WebP at publish time and keep the PNG.
WebP vs PNG at a glance
| WebP | PNG | |
|---|---|---|
| Compression | Lossless: optional | Lossless: always |
| Transparency | Yes | Yes |
| Animation | Yes | No |
| Keeps EXIF in ConvertX | Yes | Yes |
| ConvertX reads it | Yes | Yes |
| ConvertX writes it | Yes | Yes |
| Extensions | .webp | .png |
WebP: Google's web format: about a third smaller than JPG, with optional transparency and lossless mode. PNG: Lossless with transparency. Perfect for graphics, wasteful for photos.
Choose WebP when
- Published web graphics, icons and screenshots.
- App assets where size matters.
Choose PNG when
- Working files you edit again.
- Hand-offs to designers, printers or older software.
- Universal compatibility with no fallback.
File size
Lossless WebP is usually 20–40 % smaller than a well-compressed PNG. Lossy WebP can be 70–90 % smaller for photographic PNGs, at a small quality cost.
Converting between them, offline
ConvertX converts on your device with no upload, in batches, and strips location data by default.
Frequently asked questions
Is WebP really lossless?
In lossless mode, yes: pixels are identical to the PNG. ConvertX's compressor "Exact quality" mode writes lossless WebP; the converter's quality setting is lossy.
Does WebP keep partial transparency?
Yes, full alpha, including soft shadows.
Why would I convert WebP back to PNG?
To edit it in a tool that lacks WebP support, or to meet a PNG-only requirement.